Dodging a gloomy weather forecast, a SpaceX Falcon 9 rocket roared into space this afternoon to begin a critical resupply mission to the International Space Station and test a revolutionary booster stage recovery system that could change the economics of the space launch industry. Falcon successfully placed another of the company’s Dragon spacecraft into low Earth orbit and set it on course for rendezvous and capture by the Expedition 39 crew Sunday morning, bringing over two tons of science experiments and supplies to the orbiting laboratory.

Facing an instantaneous launch window, the 224 foot tall Falcon 9 rocket blasted off exactly on time at 3:25:21 p.m. EDT from Space Launch Complex 40 at Cape Canaveral Air Force Station. Carrying Dragon with a full load of supplies for the International Space Station, the vehicle rose slowly at first, then quickly accelerated away from the pad and disappeared above the clouds that had threatened to delay the launch.

Thundering skyward as it headed over the Atlantic Ocean, Falcon reached the speed of sound in just over one minute under the power of its 9 Merlin 1D first stage engines before the 12 foot diameter first stage shutdown and separated two minutes into flight. The second stage and its single Merlin 1D engine then fired for the remaining 8 minutes of powered flight, paralleling the East Coast of the U.S. and placing Dragon on an orbital trajectory to intercept ISS in two days.

The mission is the company’s third contracted cargo delivery flight to the station under a $1.6 billion NASA Commercial Resupply Services contract. SpaceX will conduct a total of 12 supply runs to ISS during its contract with NASA and is vying for a follow-on contract that is expected to result from the decision to extend the life of the station through at least 2024.

SpaceX Falcon 9 / Dragon Launch Coverage From NASA TV

In addition to Dragon, Falcon carried five small research satellites known as CubeSats that were deployed after reaching orbit. The small satellites are part of NASA’s Educational Launch of Nanosatellite and involved more than 120 students in their design, development and construction.

One of the satellites, PhoneSat 2.5, is the third in a series of CubeSat missions designed to use commercially available smartphone technology as part of a low-cost development effort to provide basic spacecraft capabilities. Another of the small satellites, SporeSat, is designed to help scientists study the mechanisms by which plant cells sense gravity — valuable research in the larger effort to grow plants in space.

Also on board is KickSat, which is a unique crowdfunded CubeSat carrying 104 tiny “Sprite” satellites inside, each one paid for by a crowdfunding contributor. The Sprites will be ejected as soon as May 4 after which they will orbit the Earth for a few days before re-entering and burning up. Each Sprite contains a solar cell and radio transmitter whose signal can be picked up by amateur radio.

Of course, the most important cargo is carried inside Dragon bound for the space station. Dragon’s cargo will support more than 150 experiments to be conducted by the crews of ISS Expeditions 39 and 40, along with more mundane but equally important supplies for the crewmembers.

“SpaceX is delivering important research experiments and cargo to the space station,” said William Gerstenmaier, NASA associate administrator for Human Exploration and Operations. “The diversity and number of new experiments is phenomenal. The investigations aboard Dragon will help us improve our understanding of how humans adapt to living in space for long periods of time and help us develop technologies that will enable deep space exploration.”

The scientific payloads on Dragon include investigations into efficient plant growth in space, human immune system function in microgravity, Earth observation, and a demonstration of laser optics communication. Also being delivered is a set of high-tech legs for Robonaut 2, which will provide the humanoid robot torso already aboard the orbiting laboratory the mobility it needs to help with regular and repetitive tasks inside the space station.

Dragon also will deliver a second set of investigations sponsored by the Center for the Advancement of Science in Space (CASIS), which manages the portion of the space station that is designated a U.S. National Laboratory. The investigations include research into plant biology and protein crystal growth, a field of study experts believe may lead to beneficial advancements in drug development through protein mapping.

Falcon’s launch had been delayed by spacecraft contamination concerns, an outage of a critical tracking radar system on the Air Force Eastern Range and a first stage helium leak four days ago. Finally, with everything ready for launch, it appeared throughout most of the countdown that weather, in particular thick clouds and rain, would force another postponement. Fortunately, as the count progressed toward T-0, the weather cleared just enough for launch.

Col. Robert Pavelko, vice commander, 45th Space Wing, who also served as the Launch Decision Authority for this launch, praised the work of all those involved in making this launch a success.

“Once again, we are proud to work hand-in-hand with SpaceX and NASA, as well as all our other mission partners in making this launch another success story coming from the Eastern Range,” he said.

Dragon will be grappled at 7:14 a.m. on Sunday, April 20, by Expedition 39 Commander Koichi Wakata of the Japan Aerospace Exploration Agency, using the space station’s robotic arm to take hold of the spacecraft. NASA’s Rick Mastracchio will support Wakata in a backup position.

Dragon is scheduled to depart the space station May 18 for a splashdown in the Pacific Ocean, west of Baja California, bringing from the space station nearly 3,500 pounds of science, hardware, crew supplies and spacewalk tools.

Dragon is loaded with 2.4 tons of payloads and cargo in its pressurized cabin and, for the first time, in the unpressurized trunk as well. The total weight of pressurized cargo is 3347 pounds of which science experiments comprise 1576 pounds. Crew supplies total 1049 pounds and the remainder of pressurized cargo contains station hardware and EVA equipment.

The Optical Payload for Lasercomm Science (OPALS) investigation tests the use of laser optics to transfer information to the ground. The switch from radio frequency to a laser beam could improve communication data rates by a factor of 10 to 100 and stands to increase the amount of data future missions can send using the same power resources.

VEGGIE is a deployable plant growth unit capable of producing salad-type crops to provide the crew with appetizing, nutritious, and safe, fresh food and support crew relaxation and recreation. The VEGGIE unit provides lighting and nutrient delivery, but uses the cabin environment for temperature control and as a source of carbon dioxide to promote growth. VEGGIE’s growth volume will be the largest volume available to date for plant growth on the space station, which will enable growth of larger plants than was previously available due to size restrictions.

The T-Cell Activation in Space investigation, which is funded by the National Institutes of Health, seeks to identify the defect in T-cell activation, an immune response used to fight foreign antigens, during microgravity exposure. Identifying this defect may someday inhibit the decline of the immune system as a normal part of the aging process.

The HDEV investigation places four commercially available high definition cameras on the exterior of the space station for use in streaming live video of Earth for online viewing. The cameras are enclosed in a temperature-specific case and exposed to the harsh radiation of the space environment. High school students helped design some of the cameras’ components, through the High Schools United with NASA to Create Hardware program, and student teams will operate the experiment.

Dragon is also carrying 1261 pounds of unpressurized cargo.

Getting as much attention as the mission to ISS, today’s flight featured the first Falcon 9 to sport 4 landing legs around its base for a critical test leading to the eventual reuse of the rocket by flying it back to the launch site for powered soft landing.

Reusability is a key goal for SpaceX, considered critical for long-term economical access to space and enabling future plans for Mars exploration.

Not part of the NASA mission, today’s launch was a test of the landing system that guided the rocket to a relatively gentle touchdown in the ocean off the coast of Jacksonville, FL, far enough out to sea to not pose a danger if anything went wrong.

However, telemetry indicated the system worked as designed. After separating from the Falcon’s upper stage, the booster reignited three of its engines for a high-speed descent through the upper atmosphere, gradually slowing down to subsonic speed. As it approache the water, a single engine fire up to slow the stage even more and gently set it down on the water.

High seas prevented the reovery boat from being on station to pick up the stage after splashdown, but data transmitted to aircraft overhead indicated the test was successful.

“Data upload from tracking plane shows landing in Atlantic was good! Several boats enroute through heavy seas,” Musk tweeted several hours after launch. He followed that up with confirmation tha the rocket landed in the ocean alive and intact. “Flight computers continued transmitting for 8 seconds after reaching the water. Stopped when booster went horizontal.”

(Matthew Travis / Zero-G News)

[CRS-3] SpaceX Falcon 9 / Dragon Postlaunch Press Conference

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SCRUBBED! SpaceX Falcon 9 v1.1 with Dragon to ISS is scrubbed due to helium leak